Concentration, significance

Although the principal appHcation of reverse osmosis membranes is still desalination of brackish water or seawater to provide drinking water, a significant market is production of ultrapure water. Such water is used in steam boilers or in the electronics industry, where huge amounts of extremely pure water with a total salt concentration significantly below 1 ppm are required to wash siUcon wafers. 

In the last two decades experimental evidence has been gathered showing that the intrinsic properties of the electrolytes determine both bulk properties of the solution and the reactivity of the solutes at the electrodes. Examples covering various aspects of this field are given in Ref. [16]. Intrinsic properties may be described with the help of local structures caused by ion-ion, ion-solvent, and solvent-solvent interactions. An efficient description of the properties of electrolyte solutions up to salt concentrations significantly larger than 1 mol kg 1 is based on the chemical model of electrolytes. 

Allen et al. (2007) produced puffed snack foods with com starch and pregelatinized waxy starch, WPC and instantized WPC, and protein concentrations of 16%, 32%, and 40% and showed that the air cell size, extru-date expansion ratio, and water solubility index decreased proportionally as protein and com starch levels increased. Protein concentration significantly affected total soluble protein, water absorption index, and water-soluble carbohydrate. A covalent complex between amylase and protein formed in the presence of cornstarch, but protein-protein interactions appeared with the presence of low levels of pregelatinized waxy starch. 

Outside the CNS, anandamide is found in the spleen and heart at approximately 10 pmol/g (Martin, 1999). It is also localized in rat testes and uterus in concentrations significantly greater than those in the brain... 

Exposed for 35 days to 30, 250, or 3000 pg atrazine/L 100 pg/L, 3-4 weeks 1000 pg/L, 3-4 weeks The high concentration significantly enhanced peroxidase activity but did not affect growth or chlorophyll production (Lytle and Lytle 1998) Biomass reduction of 34% (Stevenson etal. 1982) Biomass reduction of 46% (Stevenson etal. 1982)... 

Figure 3. The effect of NaCl on the partitioning of Ba2+ into calcite. The presence of NaCl at approximately marine concentrations significantly lowers the value of kcBa ...

Concentrations significantly reduced (Student s f-test, P<0.05) compared with snails on L diet. 

If Km for an endogenous substrate is known, then it establishes an approximate value for the endogenous concentration of that substrate. This is because it would not make sense kinetically or metabolically for a substrate to be present at concentrations significantly below or above its Km value. In the former case, the majority of enzyme protein molecules, synthesized by the cell at significant metabolic cost, would be redundant, and in the latter case, the cell would be unable to respond immediately to fluctuations in substrate concentration because enzymes would approach saturation and v would thus vary only marginally with fluctuations in [S]. 

Speciation calculations can be performed for the weak acids and bases in a feshion similar to that presented earlier for Fe(III). The results of these calculations as a function of pH are shown in Figure 5.19. At the pH of seawater, the dominant species are carbonate, bicarbonate, ammonium, hydrogen phosphate, dihydrogen phosphate, and boric and silicic acid. In waters with low O2 concentrations, significant concentrations of HS can be present. 

Suboxic O2 concentrations significantly below that of the NAEC, i.e., less than 0.2 mL/L. 

Priority I Ambient concentrations significantly above primary standards. 

Priority la Ambient concentrations significantly above primary standards and due to emission from point sources. 

Priority II Ambient concentrations significantly above secondary standards. 

Geriatric Considerations - Summary Volume of distribution (Vd), clearance, and half-life are significantly altered in older adults. Lithium toxicity may occur within the usual adult therapeutic range. Older adults are likely to exhibit toxic effects at lower serum concentrations. Significantly lower doses are often efficacious for affective disorders than are used in younger adults. Monitor serum concentrations closely, increased riskof lithium toxicity when a diuretic, NSAID, or ACE Inhibitor is started in a patient already taking lithium. 

The high concentration significantly enhanced peroxidase activity but did not affect growth or chlorophyll production (Lytle and Lytle 1998) Biomass reduction of 34% (Stevenson etal. 1982)... 

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